Inter-Integrated Circuit
Formal
I2C, pronounced I-squared-C, is a serial bus that provides communication between sensors and microcontrollers such as the Arduino. It is typically used for attaching lower-speed peripheral ICs to processors and microcontrollers.
Practical
Inter-Integrated Circuit, pronounced I-squared-C, is a multi-master, multi-slave, single-ended, serial computer bus invented by Philips Semiconductor (now NXP Semiconductors). It is typically used for attaching lower-speed peripheral ICs to processors and microcontrollers. Alternatively I?C is spelled I2C (pronounced I-two-C) or IIC.
